The fire, which started on the first floor and spread to two upper floors, escalated to two alarms at about 3:45 a.m. in the 1200 block of Battery Avenue on the southern edge of Federal Hill. Everyone inside the house was able to evacuate safely.

Bobby Ohlberter, the son of the homeowners where the fire started, said he ran to the scene once he received their frantic phone call. He said they were shaken, but thankfully OK.

"Thank God they're OK. Material things don’t really matter to me. I don't care about that. Life's more important. I just had a son myself," Ohlberter said.

Many neighbors gathered on the sidewalk to see what was going on after they were awakened by the sirens and commotion.

"By the time I woke up the house was fully engulfed. I saw the flames shooting up from the roof. And at first, I went up on my deck to see what was going on but there was so much smoke you couldn't even breathe up there so I decided to walk around here to see what was going on," neighbor Isabell Obert said.

Firefighters aggressively started to fight the fire from the inside and outside but were ordered back outside as the fire intensified, making the structure unstable. WBAL-TV 11 News reporter Kim Dacey said efforts to extinguish the fire were hampered by combustible debris inside the house, which appeared to be under renovation.

"Because of all this debris inside it continued to fuel this fire, created unsafe conditions so it was mandatory for us to evacuate those members (firefighters). We just can't risk them being in such dangerous conditions," Baltimore City Fire spokesman Chief Kevin Cartwright said.

Cartwright said the fire caused a portion of the second floor to collapse onto the first floor. A firefighter who fell off a ladder suffered an ankle injury, but is expected to be OK, officials said.

Photos: Federal Hill fire displaces residents

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WBAL-TV\Kim Dacey

A firefighter suffers injuries in an intense fire that burned for hours in south Baltimore.

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